Antifibrotic effect of aloe vera in viral infection-induced hepatic periportal fibrosis

Evaluation of in-vitro antioxidant activity, acute oral toxicity, and pancreatic and hepatic protective effects of Aloe rubroviolacea flowers extract against CCl4 toxicity in a rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe rubroviolacea (Arabian Aloe) was widely cultured and commonly used in traditional medicine. Aloe species was highly recommended in folk medicine for abdominal pain, intestinal infection, intestinal colic, obesity, and gynaecological pain after childbirth.

AIM OF THE WORK

The present work aimed to conduct chemical profiling, in-vitro antioxidant activity, in-vivo oral acute toxicity study of A. rubroviolacea flowers ethanolic extract (ARFEE) along with exploring pancreatic and hepatic protective effects of ARFEE against carbon tetrachloride (CCl4) toxicity in a rat model. Molecular docking study of ARFEE and 3D structure activity relationship was also demonstrated to investigate the proposed antioxidant mechanism.

MATERIALS AND METHODS

The chemical composition was analyzed using gas chromatography-mass spectrometry (GC-MS) and thin layer chromatography (TLC) techniques. Total phenolic and flavonoid contents in ARFEE were estimated by Folin-Ciocalteu and AlCl3 colorimetric methods, respectively. In-vitro antioxidant DPPH assay was performed using ascorbic acid as a reference standard. Moreover, In-vivo acute toxicity study using fixed doses of ARFEE (0.1, 0.5, 1, 2 and 3 g/kg orally) was conducted. CCl4 toxicity was induced by using a single dose of CCl4 (1 ml/kg, i.p.) on 5th day, silymarin (50 mg/kg/day, orally) as a standard and two different doses of ARFEE (250, 500 mg/kg, orally) daily for 5 days before CCl4 injection.

RESULTS

GC-MS analysis displayed the existence of 36 chemical compounds, the majority of which were fatty acids and their esters, in addition to phytosterols. The total phenolic content of ARFEE was 25.09 ± 1.65 mg of gallic acid equivalent/g extract dry weight (mg GAE/g DW), while the total flavonoid content was 17.48 ± 0.64 mg of quercetin equivalent/g extract dry weight (mg QE/g DW). Our results showed that the ARFEE had a potential in-vitro antioxidant activity as strong as ascorbic acid. No mortality or signs of toxicity were observed after ARFEE intake. Additionally, ARFEE ameliorated CCl4 toxicity on hepatic and pancreatic tissues. Molecular docking study resulted in potent promising natural compounds contained in ARFEE with anti-oxidant potential.

CONCLUSION

Based on oral safety, good anti-oxidant and pancreato- and hepato-protective activities of ARFEE against CCl4 toxicity, ARFEE is probably a potent agent for treatment of liver ailments.

Enhanced anti-inflammatory and anti-fibrotic effects of nanoparticles loaded with a combination of Aloe vera-Moringa oleifera extracts

Metabolic associated steatohepatitis characterized by lipid accumulation, inflammation and fibrosis, is a growing global health issue, contributing to severe liver-related mortality. With limited effective treatments available, there is an urgent need for novel therapeutic strategies. Moringa oleifera, rich in antioxidants, offers potential for combating steatohepatitis, but its cytotoxicity presents challenges. Aloe vera, renowned for its cytocompatibility and anti-inflammatory effects, shows promise in mitigating these risks. Using infrared spectrometry and mass spectrometry, we identified 1586 metabolites from both plants across 84 chemical classes. By encapsulating these phytochemicals in nanoparticles, we achieved increased solubility, cytocompatibility, and gene modulation to hepatic stellate cells affected by steatohepatitis. Chemoinformatic analysis revealed bioactive metabolites, including hesperetin analogs, known to inhibit TGF-β. Our results demonstrate that these nanoparticles not only improved gene expression modulation related to metabolic associated steatohepatitis, particularly TGF-β and COL1A1, but also outperformed free compounds, highlighting their potential as a novel therapeutic approach.

Plant leads for mitigation of oral submucous fibrosis: Current scenario and future prospect

The aim of this review is to enumerate medicinal plants and their bioactive compounds that may become potential leads in the mitigation of oral submucous fibrosis (OSMF) in the forthcoming future. It is focused on pathophysiology, risk factors, current treatment regimen, potential plant leads, and future therapies for OSMF. Data were extracted from a vast literature survey by using SciFinder, Web of Science, Google Scholar, and PubMed search engines with relevant keywords. Upon literature survey, we found that the phytochemical 'arecoline' present in the areca nut is the main causative agent of OSMF condition. Currently, OSMF is treated by immunomodulatory and anti-inflammatory agents such as corticosteroids, enzymes (hyaluronidase, chymotrypsin, and collagenase), anti-inflammatory mediators (isoxsuprine and pentoxifylline), dietary supplements (vitamins, antioxidants, and micronutrients), and anti-fibrotic cytokines like interferon-gamma that provides short-term symptomatic relief to OSMF patients. However, some plant leads have been proven effective in alleviating symptoms and mitigating OSMF, which ultimately improves the quality of OSMF patients' life. We concluded that plant drugs like lycopene, curcumin, Aloe vera, colchicine, and Glycyrrhiza glabra are effective against OSMF in various in vitro and/or clinical studies and are being used by modern and traditional practitioners.

Network Pharmacology and Molecular Docking Study on the Multi-Target Mechanisms of Aloe vera for Non-Alcoholic Steatohepatitis Treatment

Non-alcoholic steatohepatitis (NASH) is a leading cause of chronic liver disease with limited treatment options. The widely distributed plant Aloe vera has shown protective effects against NASH in animals, yet the precise mechanism remains unknown. In this study, we investigated the potential mechanisms underlying the anti-NASH effects of Aloe vera using a network pharmacology and molecular docking approach. By searching online databases and analyzing the Gene Expression Omnibus dataset, we obtained 260 Aloe vera-NASH common targets. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that the common targets were strongly associated with the key pathological processes implicated in NASH, including lipid and glucose metabolism, inflammation, apoptosis, oxidative stress, and liver fibrosis. Four core proteins, AKT serine/threonine kinase 1 (AKT1), tumor necrosis factor alpha (TNFα), transcription factor c-Jun, and tumor suppressor protein p53, were identified from compound-target-pathway and protein-protein interaction networks. Molecular docking analysis verified that the active ingredients of Aloe vera were able to interact with the core proteins, especially AKT1 and TNFα. The results demonstrate the multi-compound, multi-target, and multi-pathway mechanisms of Aloe vera against NASH. Our study has shown the scientific basis for further experiments in terms of the mechanism to develop Aloe vera-based natural products as complementary treatments for NASH. Furthermore, it identifies novel drug candidates based on the structures of Aloe vera's active compounds.

Potential protective effects of Aloe vera gel on cardiovascular diseases: A mini-review

Cardiovascular diseases (CVDs) comprise the most prevalent causes of morbidity and mortality in both men and women worldwide. CVDs are associated with several risk factors such as hyperlipidemia, diabetes mellitus, hypertension, obesity, tobacco smoking and an unhealthy diet. Currently, in addition to the use of related pharmacological treatments in the management of CVDs, the investigation of other suitable healthcare approaches for these disorders such as the identification of herbal medicines has been considered in the scientific communities. Aloe vera (L.) Burm.f. is a perennial medicinal plant. The innermost leaf layer of this plant contains transparent gel, which is used as food. Pre-clinical studies have shown several biological activities of A. vera gel (AVG), including antidiabetic, lipid-lowering, antioxidant, antiinflammatory, hepatoprotective, and immunomodulatory effects. Other pharmacological activities of AVG such as anti-fibrotic, anti-hypertensive, and anti-atherosclerotic effects have been reported. Moreover, several clinical studies have demonstrated the ameliorating effects of AVG on some markers of CVDs risk factors. Thus, this study was conducted to review clinical trials besides in vitro and in vivo studies on the cardiac beneficial effects of AVG. However, further high-quality studies are needed to firmly establish the clinical efficacy of the plant.

The Effect of Aloe Vera Juice on Liver Enzymes and Hepatic Structure in a Healthy Population

BACKGROUND

There have been isolated reports of Aloe vera hepatotoxicity, usually manifested by transient liver function test abnormalities. While the European Food Safety Authority has recommended that whole leaf products containing the rind of the Aloe vera plant should not be used for human oral consumption, those Aloe vera gels made of the treated plant pulp alone are considered safe for daily consumption, provided recommended quantities are not exceeded. We aimed to assess hepatic function in healthy volunteers consuming the purified plant pulp Aloe vera gel over a 60 day period.

METHODS

35 healthy volunteers consumed the maximum recommended daily dose of 2 oz (57 mL) of Aloe vera gel twice daily for a total of 60 days. The participants attended an initial baseline visit where biochemical measurements of hepatic synthetic function were obtained, and each volunteer underwent hepatic ultrasound with elastography, superb microvascular imaging and image quantification. Further visits were undertaken at days 30 and 60 to undergo the same biochemical and imaging measurements of liver function to monitor if there were any changes in the parameters measured.

RESULTS

Seven volunteers failed to complete the study, citing unspecified gastrointestinal upset and/or an inability to tolerate the taste of the Aloe vera gel. None of these individuals had disturbance of biochemical or imaging parameters of hepatic function. Of the remaining 27 healthy volunteers, none had a change in either biochemical indices of liver function, or of ultrasound markers of hepatic blood flow or liver tissue elasticity after 60 days of Aloe vera gel consumption. However, there was a non-significant reduction in serum homocysteine levels as the only detectable change in the cohort.

CONCLUSIONS

Despite reports of potential hepatotoxicity with some Aloe vera products, in this healthy cohort, extended consumption of purified plant-pulp Aloe vera gel did not have any detectable effects on hepatic function, blood flow or tissue elasticity.

Protective effects of Aloe sterols against UVB-induced photoaging in hairless mice

BACKGROUND

Aloe vera is a traditional medical plant whose gel has been widely used in skin care. Previously, we have identified Aloe sterols from Aloe vera as active ingredients. This study investigated the protective effects of Aloe sterols without polysaccharides, against ultraviolet B (UVB)-induced skin photoaging in mice using Aloe vera gel extract (AVGE) obtained by supercritical fluid extraction.

METHODS

Aloe vera gel extract was supplemented in the diet (12 or 120 ppm), and HR-1 hairless mice were exposed to UVB irradiation for 7 weeks. Skin measurements and histological and analytical studies were performed.

RESULTS

Repeated UVB irradiation induced rough wrinkling of skin with water content reduction and hyperkeratosis. AVGE administration resulted in the significant improvement of UVB-induced skin dryness, epidermal thickness, and wrinkle formation. The AVGE group also suppressed the degenerations of dermal collagen fibers and the appearance of cutaneous apoptosis cells induced by UVB. Furthermore, AVGE administration reduced the excess elevation of pro-inflammatory cytokines (IL-1β and TNF-α) and matrix metalloproteinases (MMP-2, MMP-9, MMP-12, and MMP-13) in UVB-exposed skin.

CONCLUSION

The dietary ingestion of Aloe sterols protected against chronic UVB damage in mouse skin, and our results suggest that Aloe sterols may prevent skin photoaging through the anti-inflammation and MMP regulation.

Therapeutic effects of Aloe spp. in traditional and modern medicine: A review

Traditional medicine is a useful guide in medical sciences. In the Islamic Iranian traditional medicine, the medicinal properties of many plants have been mentioned that could be exploited in drug discovery. We aimed to explore the nature and properties of Aloe spp. As described in some major Islamic traditional texts including Ferdows al-Hekmah fi'l-Tibbe (The Paradise of Wisdom in Medicine), Al-Hawi fi'l-Tibb (Comprehensive Book of Medicine), Kamel al-Sanaat al-Tibbyyah (Complete Book of the Medical Art), Al-Qanun fi'l-Tibb (Canon of Medicine), Zakhireh Kharazmshahi (Treasure of Kharazmshah), and Makhzan al-Adwiah (Drug Treasure), and assess the conformity of traditional medicine instructions with the findings of modern pharmacological studies. Gastrointestinal activities, hepato-protective properties, beneficial effects against skin problems such as wounds, injuries, and infective diseases are among the most frequently mentioned properties of Aloe spp. Several activities of Aloe spp. described in traditional medicine have been the subject of recent in vitro and in vivo studies as well as clinical trials. Owing to the positive findings, different preparations of Aloe spp. are now present in pharmaceutical markets such as Aloe cosmetic products. On the other hand, there are many traditional therapeutic effects of Aloe spp. which have not been studied and require confirmatory experimental or clinical investigations. It is hoped that the present study could stimulate further research on the unexplored aspects of the medicinal properties of Aloe spp.

Aloin Protects Skin Fibroblasts from Heat Stress-Induced Oxidative Stress Damage by Regulating the Oxidative Defense System

Oxidative stress is commonly involved in the pathogenesis of skin damage induced by environmental factors, such as heat stress. Skin fibroblasts are responsible for the connective tissue regeneration and the skin recovery from injury. Aloin, a bioactive compound in Aloe vera, has been reported to have various pharmacological activities, such as anti-inflammatory effects. The aim of this study was to investigate the protective effect of aloin against heat stress-mediated oxidative stress in human skin fibroblast Hs68 cells. Hs68 cells were first incubated at 43°C for 30 min to mimic heat stress. The study was further examined if aloin has any effect on heat stress-induced oxidative stress. We found that aloin protected Hs68 cells against heat stress-induced damage, as assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assay. Aloin protected Hs68 cells by regulating reactive oxygen species production and increasing the levels of glutathione, cytosolic and mitochondrial superoxide dismutase. Aloin also prevented the elevation of thiobarbituric acid reactive substances and the reduction of 8-OH-dG induced by heat stress. These results indicated that aloin protected human skin fibroblasts from heat stress-induced oxidative stress damage by regulating the oxidative defense system.

Aloe vera attenuated gastric injury on indomethacin-induced gastropathy in rats

AIM: To evaluate the protective effects of Aloe vera on gastric injury in rats with indomethacin (IMN)-induced gastropathy.

METHODS: Male Sprague-Dawley rats were randomly divided into three groups. Group 1 (control, n = 6) was given distilled water (DW) orally. Group 2 (IMN, n = 6) was given oral IMN (150 mg/kg) dissolved in 5% sodium bicarbonate (NaHCO₃^-) at time 0 and 4 h. Group 3 (Aloe vera-treated, n = 6) was given oral Aloe vera (150 mg/kg) dissolved in DW and IMN at time 0 and 4 h. Eight hours later, the stomach was removed to determine gastric malondialdehyde (MDA), the number of interleukin (IL)-18 positive stained cells (%) by immunohistochemistry, and for histopathological examination. Then, the serum was collected to determine tumor necrosis factor (TNF)-α and cytokine-induced neutrophil chemoattractant (CINC)-1 by sandwich enzyme linked immunosorbent assay method.

RESULTS: In the IMN group, serum TNF-α, CINC-1 and gastric MDA were significantly increased when compared to the control group (27.78 ± 1.52 pg/mL vs 85.07 ± 49.11 pg/mL, P = 0.009; 104.55 ± 45.80 pg/mL vs 1054.70 ± 20.38 pg/mL, and 1.74 ± 0.21 nmol/mg vs 9.36 ± 1.07 nmol/mg protein, P = 0.000, respectively). The mean level of TNF-α, CINC-1 and gastric MDA in the Aloe vera-treated group were improved as compared with the IMN group (85.07 ± 49.11 pg/mL vs 35.19 ± 1.61 pg/mL, P = 0.021; 1054.70 ± 20.38 pg/mL vs 813.56 ± 239.04 pg/mL, P = 0.025; and 9.36 ± 1.07 nmol/mg vs 2.67 ± 0.64 nmol/mg protein, P = 0.000, respectively). The number of IL-18 positive stained cells (%) in the gastric epithelial cells of the IMN group was significantly higher than the control group (5.01% ± 3.73% vs 30.67% ± 2.03%, P = 0.000, respectively). In contrast, Aloe vera treatment decreased the number of IL-18 positive stained cells (%) significantly when compared with the IMN group (30.67% ± 2.03% vs 13.21% ± 1.10%, P = 0.000, respectively). Most rats in the IMN group developed moderate to severe gastric inflammation and erosions. The gastric erosions and neutrophil infiltration scores were significantly reduced in the Aloe vera-treated group.

CONCLUSION: Aloe vera attenuated IMN-induced gastropathy in rats by the reduction of oxidative stress, inflammation, and improvement of gastric histopathology.

Herbal medicines in Brazil: pharmacokinetic profile and potential herb-drug interactions

A plethora of active compounds found in herbal medicines can serve as substrate for enzymes involved in the metabolism of xenobiotics. When a medicinal plant is co-administered with a conventional drug and little or no information is known about the pharmacokinetics of the plant metabolites, there is an increased risk of potential herb-drug interactions. Moreover, genetic polymorphisms in a population may act to predispose individuals to adverse reactions. The use of herbal medicines is rapidly increasing in many countries, particularly Brazil where the vast biodiversity is a potential source of new and more affordable treatments for numerous conditions. Accordingly, the Brazilian Unified Public Health System (SUS) produced a list of 71 plant species of interest, which could be made available to the population in the near future. Physicians at SUS prescribe a number of essential drugs and should herbal medicines be added to this system the chance of herb-drug interactions further increases. A review of the effects of these medicinal plants on Phase 1 and Phase 2 metabolic mechanisms and the transporter P-glycoprotein was conducted. The results have shown that approximately half of these medicinal plants lack any pharmacokinetic data. Moreover, most of the studies carried out are in vitro. Only a few reports on herb-drug interactions with essential drugs prescribed by SUS were found, suggesting that very little attention is being given to the safety of herbal medicines. Here we have taken this information to discuss the potential interactions between herbal medicines and essential drugs prescribed to Brazilian patients whilst taking into account the most common polymorphisms present in the Brazilian population. A number of theoretical interactions are pinpointed but more pharmacokinetic studies and pharmacovigilance data are needed to ascertain their clinical significance.

Aloe vera attenuated liver injury in mice with acetaminophen-induced hepatitis

BACKGROUND

An overdose of the acetaminophen causes liver injury. This study aims to examine the anti-oxidative, anti-inflammatory effects of Aloe vera in mice with acetaminophen induced hepatitis.

METHODS

Male mice were randomly divided into three groups (n = 8 each). Control group were given orally distilled water (DW). APAP group were given orally N-acetyl-P-aminophenol (APAP) 400 mg/kg suspended in DW. Aloe vera-treated group were given orally APAP and Aloe vera (150 mg/kg) suspended in DW. Twenty-four hours later, the liver was removed to determine hepatic malondialdehyde (MDA), hepatic glutathione (GSH), the number of interleukin (IL)-12 and IL-18 positive stained cells (%) by immunohistochemistry method, and histopathological examination. Then, the serum was collected to determine transaminase (ALT).

RESULTS

In APAP group, ALT, hepatic MDA and the number of IL-12 and IL-18 positive stained cells were significantly increased when compared to control group (1210.50 ± 533.86 vs 85.28 ± 28.27 U/L, 3.60 ± 1.50 vs 1.38 ± 0.15 nmol/mg protein, 12.18 ± 1.10 vs 1.84 ± 1.29%, and 13.26 ± 0.90 vs 2.54 ± 1.29%, P = 0.000, respectively), whereas hepatic GSH was significantly decreased when compared to control group (5.98 ± 0.30 vs 11.65 ± 0.43 nmol/mg protein, P = 0.000). The mean level of ALT, hepatic MDA, the number of IL-12 and IL-18 positive stained cells, and hepatic GSH in Aloe vera-treated group were improved as compared with APAP group (606.38 ± 495.45 vs 1210.50 ± 533.86 U/L, P = 0.024; 1.49 ± 0.64 vs 3.60 ± 1.50 nmol/mg protein, P = 0.001; 5.56 ± 1.25 vs 12.18 ± 1.10%, P = 0.000; 6.23 ± 0.94 vs 13.26 ± 0.90%, P = 0.000; and 10.02 ± 0.20 vs 5.98 ± 0.30 nmol/mg protein, P = 0.000, respectively). Moreover, in the APAP group, the liver showed extensive hemorrhagic hepatic necrosis at all zones while in Aloe vera-treated group, the liver architecture was improved histopathology.

CONCLUSIONS

APAP overdose can cause liver injury. Our result indicate that Aloe vera attenuate APAP-induced hepatitis through the improvement of liver histopathology by decreased oxidative stress, reduced liver injury, and restored hepatic GSH.

Therapeutic effect of Soshiho-tang, a traditional herbal formula, on liver fibrosis or cirrhosis in animal models: a systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Liver fibrosis has been recognized as a major lesion of the liver that leads to liver cirrhosis at the end stage. Soshiho-tang (SST) has been used to improve liver fibrosis/cirrhosis by ameliorating fibrosis-specific markers. This study aimed to assess the efficacy of SST on liver fibrosis/cirrhosis through a systematic review of the literature and meta-analysis using animal models.

MATERIALS AND METHODS

Studies of SST treatment in liver fibrosis/cirrhosis-induced animal models were searched by electronic data bases. The quality of the studies included was assessed and the efficacy of SST was evaluated based on markers from liver tissues and serum.

RESULTS

Among the 838 studies identified in the literature search, 20 studies that met the inclusion criteria were included in the analysis. SST significantly reduced the elevated levels of fibrosis markers, such as the degree of fibrosis, hydroxyproline, hyaluronic acid, transforming growth factor-β1, and procollagen III in liver tissues, and aspartate aminotransferase, alanine aminotransferase, procollagen III, tissue inhibitor of metalloproteinase-1, and type IV collagen in the serum.

CONCLUSIONS

SST was effective in decreasing pathologically increased markers in animal models of liver fibrosis/cirrhosis. A larger-scale of animals, well-designed animal study is expected to improve the methodological quality, heterogeneity, and potential biases of the meta-analysis.

Correlation of nuclear factor κB expression with α-SMA and collagen Ⅲ expression in hepatic fibrosis in rats

AIM: To investigate the correlation of expression of nuclear factor κB with that of α-smooth muscle actin (α-SMA) and collagen Ⅲ in hepatic fibrosis in rats.

METHODS: Thirty-two male SD rats of SPF grade were divided randomly into control group and model group. Hepatic fibrosis was induced in rats by injecting carbon tetrachloride. The mRNA and protein expression of NF-κB, α-SMA, and collagen Ⅲ was examined using reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. The correlation of NF-κB expression with α-SMA and collagen Ⅲ expression was then analyzed.

RESULTS: NF-κB, α-SMA and collagen Ⅲ were lowly expressed in normal liver tissue. After injection of carbon tetrachloride, the expression of NF-κB, α-SMA and collagen Ⅲ mRNAs and proteins began to increase at week 2 and was significantly higher at weeks 4 and 6 (both P < 0.05), showing a gradually rising trend. There was a positive correlation between the expression of NF-κB and that of α-SMA and collagen Ⅲ (both P < 0.05).

CONCLUSION: NF-κB plays an important role in the pathogenesis of hepatic fibrosis.